DE1719216C - Process for the production of polyurethane foams - Google Patents

Description

The invention relates to a process for the production of polyurethane foams from diimethylbenzene-w.fo'-diisocyanate and one with a low molecular weight polyisocyanate in deficit modified polyether polyol having a hydroxyl number of about 25 to 75 or a polyester polyol with a hydroxyl number of about 25 to 75 in the presence of amino alcohols and a propellant which is characterized in that one is in the presence

a) a compound of the general formula

RR RR

X '-Sn - O - Sn- X "

X "-Sn -O - Sn-X ^{1 v} Alkylcarbonvlox> groups with 2 to 17 carbon atoms are NCO or NCS groups and R is a skdermolecular alkyl radical with a maximum of 4 carbon atoms. And

b) a monoamino alcohol with a maximum of 4 carbon atoms is working.

Polyurethane foams are known to be made from aromatic polyisocyanates (e.g. toluene isocvanate or diphenylmethane diisocyanate) and polyols or polyester poles produced. However, the foams produced in this way gave when exposed to the atmosphere, severely limiting their practical application

^W1 po "lvurethane. V under Vervsendung, y aliphatic diisocyanate ^ *., Hexamethylene diisocyanate) as Isocvanatkomponente turn yellow on the other hand not, will o made from aromatic diisocyanate to the extent such as polyurethanes, ·, but the former are in. inferior to lead physical properties of the latter sharply. Further, it is practically unmöslich. PolyurethanscnaumsiOne unier use of aliphatic diisocyanates :! in a ₅ practice to manufacture, since the reactivity of the aliphatic diisocyanates noted with polyols, is worth low. an industrially feasible process for the preparation of non-yellowing: soft, elastic to flexible polyurethane foams with good physical properties; this has long been desired.

Comparative attempts were made to produce \ or. Polyurethane foams carried out in the case of which catalysts from the German Auslegeschnftc * i 109 882 and 1091 324 were used. .. At d · Verwendline of known organotin Katah catalysts for "the preparation of polyurethane foam materials as ζ B Dibuulzinndilaurat (Examples 1 to ·: ■ German Auslegeschrift L 109 882 and Example 2 of the German Auslegeschrift 1,091,324) was the formation of of polyurethane foams made from dimethylben / ol-TM-diisocyanate according to the invention. Even when using the catalyst combination of dibutyltin dilaurate and octylstannoate and aliphatic diisocyanate compounds from the German Auslegeschrift 1 091 324 in the method of the invention, no foam could be formed. Du.ch die Simultaneous use of the monoamine alcohols mentioned during the production of the polyurethane foams makes it possible to effectively prevent the occurrence of cracks in the foam: Dimethylbenzene-f'Vü'-diisocyanate has the formula

R R

R R

where X ', X'
OH groups,

X '"and X ^IV for halogen radicals, low molecular weight alkoxy groups

- - _rr . . _

with a maximum of 4 carbon atoms, formyloxy-, CH ₂ NCO CH ₂ NCO

This formula includes 1,2-dimethylbenzene-w, w'-diisocyanate. 1,3-dimethylbenzene-c), (o'-diisocyanate, 1,4-dimethylbenzene-nj, ri / diisocyanate and mixtures thereof. In practice it is advantageous to use a mixture of the 1,3-isomer and the 1,4-isomer, in particular a mixture of 60 to 90 percent by weight of the Ι, Γ isomer. and 40 to 10 weight percent des 1,4-isomers to be used.

Suitable polyols for the purposes of the invention are suitable isocyanate-modified polyether polyols or polyester

polyols with two or more terminal hydroxyl groups and a Hydroxy 'number of about 25 to 75, preferably from about 30 to 65.

Isccyanite-modified polyether polyols are suitable. by reacting an excess of the polyether polyols mentioned below with a low molecular weight polyisocyanate. z. B. Toluvicndii ^ cyanate. Diphenylmeihandiisocyanai or Dimethvlp'enzo! -C » ('-c'iisocyanat. with heating in the presence of the catalyst for the formation of \ or L'rethanhir, -dunsen. have been received.

From FVlyätherpolyole> rruchte production of isocyanaimodilizierten Pohiiiherpolyole products obtained are suitable for non-bean here dun.li addition polymerization of alkylene oxides (eg ethylene oxide. Propylene oxide, Butyierioxyd.'StyioIov. I or mixtures thereof) with niedrismolekul-ire · ^"1 . Polyhydric alcohols that serve as initiators (e.g. ethylene glycol, diethylene glycol. Propylene glycol. ':, 1;,: .. τ; η. Trimethylolpropane. Hexanetriol.'Pentaerynr; ·. Sorbitol. Sucrose. Mannitol. Sorbitol or dcrJn Ce: -he) or with amines (e.g. ethylenediamine. Pro: · .enediamine. Ethanol or mixtures thereof), μη;. ·: alkaline or acidic conditions. These pe ·: · ..i.herpolyols can be used in in a manner known per se kc.'i , e.g. according to the method published by v. ran G. Gaylord in "High Polymers", Vol. XII. TV; Polyethers Part 1 "(1963) by Ir / -jience PuLüshers.

■ ·. ·· ■ π the isocyanate- modifying; n polyether polyols i- ..iv. most advantageous -as Pohäiherpolyd. dv rr .. ' Oimethylb £ nzo, -cj, ff)' - diisocy nat modified is ii :: 'has been produced. by the above (· ':; mth polyether polyol under heating in Over-S ^: .ti with Dimethy benzene-o;, "' -.. diisoe \ anai in Gesenv.- of Octaalkyl-stannoxans the following p; Riiel ( H) had been implemented.

\ ls Polyesterpolyols are suitable for the purposes of {■ •! indiing products that are not subject to any claims V. can also be obtained by converting nicdrigro'lekularen polyhydric alcohols (e.g. Athylenf '.;. col. Propylene glycol, diethylene glycol. Triethylenjiiykol, Butylene glycol, trimethylolpropane, glycerine, liexantriol, pentaerythritol or mixtures of these Alcohols) with polycarboxylic acids (e.g. succinic acid, tilutaric acid, pimelic acid, suberic acid, azelaic acid. Sebacic acid, maleic acid, fumaric acid, itaconic acid, phthalic acid, isophthalic acid. Terephthalic acid or Anhydrides or mixtures of these acids. Suitable «. Also polyactone polyester polyols that are manufactured are made by reacting a lactone with a polyfunctional initiator by heating in the presence or absence of a catalyst. Suitable initiators are, for example, diols (e.g. Ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol or xylene diol), diamines (e.g. ethylenediamine, Phenylenediamine or xylylenediamine), amino alcohols (e.g. ethanolamine or p-aminophenylethyl alcohol), Polyols (e.g. glycerol, trimethylolpropane, pentaerythritol, sorbitol, sucrose, mannitol, sorbitol or Oxyalkylene polyols) or polyamines (e.g. diethanolamine or diisopropanolamine).

For the purposes of the invention, for example, lactones of the general formula are suitable

R'CH (CR ' ₂ ) "C = O O

Herein, η is an integer of at least 3, where at least ;; -f- 2 radicals R are hydrogen and the remaining radicals FL are alkyl, cycloalkyl. Alkoxy or aromatic hydrocarbon radicals with a ring, none of the substituents contains more than about 12 carbon atoms and the total number of carbon atoms in the substituents of a lactone ring is not more than 12. Typical examples are: o-valerolactone, y -Caprolactone. Γ-enantholactones. »Y-Caproiacton,

ίο / i-ethyl rVvalerolactone or dimethylcaprolactone.

The polyesterpulyols can be known per se Manufactured in a manner as described, for example, in the following literatures: »Polyesters and! heir Application «. 3rd Edition. April 1959.

published on Bjorksten Research Lab. Inc. Inc. New York. USA., And in the USA. Patent documents 2 890 208. 2 977 885 and 2 933 478.

In the process according to the invention, the octaalkylstannoxanes of the general as catalysts Formula used

R R

R R

X ^f - Sn-O - Sn-X "

X '"- Sn-O-Sn-X ^I

R R

R R

This contains X '. X ". X" and X ^IV for halogen radicals (e.g. Cl, Br, J »der F), OH groups, alkoxy radicals with no more than 4 carbon atoms, formyloxy radicals, alkyicarbonyloxy radicals with 2 to 17 carbon atoms, NCO or NCS groups. and R stands for an alkyl radical ^{; iD} with not more than 4 carbon atoms. These compounds have previously been referred to simply as Ve'.raalkyldistannoxanes of the formula

X '-S _n - O —S ₁₁ -X "

referred to, however, it has been shown that the compound under normal conditions in the form of a dimer. namely the octaalkylstannoxane of the first-mentioned formula is present. Therefore, in the Description of the connection as there ;; Dimers, namely

referred to as octaalkylstannoxane.

The stannoxanes can be produced, for example, by the process described in »Journal of Organometallic Chemistry "Vol. 1. No. 1, pp. 81 to 88 (1963).

As examples of typical octaalkylstannoxanes necessary for the practical implementation of the process are most appropriate according to the invention, the following may be mentioned:

So 1. Octamethyltetrachlorostannoxane

2. Octabutyltetrachlorostannoxane

3. Octabutyltetrabromostannoxane

4. Octabutyldichlorodihydroxystannoxane

5. Octabutyltetraacetoxystannoxane 6. Octaäthyltetraformyloxystannoxane

7. Octabutyldiacetoxydihydroxystannoxane

8. Octabutyltetralauroyloxystannoxane

9. Octapropyltetrastearoyloxystannoxane

10. Octabutyl tetraisocyanate stannoxane

H. Octaethyl diisocyanate dihydroxystannoxane

12. Octamethyl diisocyanate dimethoxystannoxane

13. Octabutylletraisole thiocyanate stannoxane

14. Octabutyl diisothiocyanate diethoxystannoxane

15. Octamethyldichlorodimethoxystannoxane

16. Ociaäthyldibromdiälhoxystannoxan

17. Octabutyldiaceto.vydiälhoxystannoxun

According to the invention, a suitable amount of a monoamino alcohol having 1 to 4 carbon atoms is in the Reaction system present, whereby cracking in the formed polyurethane foam is prevented. Examples of suitable monoamino alcohols are 2-aminoethanol and 2-aminopropan-1-ol. 1-aminopropan-2-ol. 2-aminobutan-1-ol. l-aminopropane-3-o! or 3-aminobiitan-1-ol. Of which i-> t 2-aminoethano] most advantageous for practical use.

Propellants known per se can be used for the process according to the invention. For example, water is suitable. Compounds which form water during the reaction, halogenated hydrocarbons with a relatively low boiling point, v. B. dichlorodifluoromethane or trichloromonofluoromethane, or compounds which form nitrogen gas during the reaction, e.g. B. Azo compounds.

The amount of the catalyst is about 0.05 to 2.0. Preferably about 0.1 to 1.5 parts by weight per 100 parts by weight of the polyol component.

The amount of the monoamino alcohol to be used according to the invention varies with the one used Polyol and with the reaction conditions. In general however, it is in the range from about 0.1 to 5, in particular from about 0.3 to about 3.0 parts by weight per 100 parts by weight of the polyol component.

For carrying out the process according to the invention, the sole use of the Sn catalyst can be used are sufficient for the formation of polyurethane foams with desired properties, however tertiary amines can of course also be used in addition. Suitable tertiary amines are for example triethylamine, N.N, N'- or N'-TetraiTict liy I-1.3-butanediamine.

The reaction can be carried out, for example, in the presence of foam stabilizers (e.g. silicone oil, polydimethylsiloxane or alkylisilane-polyoxyalkylene-Co- |) o! ymcrcn. non-icnogenic surfactants (e.g. sorbitol monoslearate, glycine monooleal or castor oil-ethylene oxide adduct]). Paints. Additives. Enhancer fillers, dyes, antioxidants and flame retardants will. The details of the implementation of the process for the production of polyurethane foams according to the invention can similar tein as in the known methods, for example in “High Polymers, Vol. XVI. Polyurethanes: Chemistry and Technologie I, Chemistry «by Satinders 1 · "r i s c h (1962), edited by Interscicncc Publishers.

In the full examples, parts are parts by weight unless otherwise specified.

example 1

To 1 (X) parts of polycaprolactone polyester polyol (OH number 55.5, Siurezalil 0.6, white waxy substance, which has been obtained by reacting / -caprolactone with trimelhylolpropane according to the method of US Pat. No. 2,890,208, are given below vigorous stirring at 45 2.0 parts of the castor oil-ethylene oxide adduct, which has been obtained by reacting ethylene oxide with castor oil, 0.5 parts of 2.5-di-tert-amylhydroquinone, 3.0 parts of water, 1.1 parts of 2-aminoethanol and 0.16 parts OctabutyltetralauroU-oxystannoxan added in this order the mixture is ^m;. t 46.5 parts of dimethylbenzene · wr / · Jiisocyanat mixed (mixture of 75 parts of the 1,3-isomers and "25 parts of the 1,4-isomers) with vigorous stirring where a reaction takes place, which results in a white, soft polyurethane foam.

Comparison test 1

The ^; The experiment carried out in Example 1 is repeated, but without 2-Amir.jäthanol and using triethylenediamine (0.3 parts) and Slanru 2-ethylhexoate (0.7 parts) on the part of OetabuUi tetralauroyloxystannoxan (0.16 Parts) and using 42 parts of dimethylbenzene-o.'o'-diiso cyanate. Fail during the foaming reaction; however, the foam formed completely collapses, so that no foam is obtained.

Example 2

To 100 parts of polycaprolactone polyester polyol with the properties mentioned in Example] with vigorous stirring at 45 ° C. 2.0 parts of the castor oil-ethylene oxide adduct mentioned in Example 1.

0.5 parts of 2.5-di-tert.-amylhydrochloride, 2.0 parts of water, 0.5 part of 2-aminoalhanol and 2.0 parts of octabutyltetraacetoxystannoxane are given in this order. The mixture is mixed with 33.5 parts of dimethylbenzene- «(o'-diisoxyanate (mixture of 70 parts of the 1,3-isomer and 30 parts of the 1,4-ionizing) under vigorous Stir mixed, whereby one reaction takes place, the results in a white soft polyurethane foam.

Comparative experiment 2

The experiment described in Example 2 is repeated without adding 2-aminoethanol. The one here formed polyurethane foam has large cracks.

Example 3

To 100 parts of polycaprolactone polyester polyol (OH number 5j, 5 acid number 0.6) [white, wax-like substance, made from c-caprolactone and glycerine according to USA.-Palcntschrift 2 890 208] with vigorous stirring at 45 ° C 2.0 parts of the in Example 1 said castor oil-ethylene oxide adduct, 0.5 part of 2,5-di-tert.-amylhydroquinone, 2.5 parts of water, 1.2 parts of 2-aminoethanol and 0.15 parts of oclabulyldichlorodihydroxyslannoxane given in that order. The mixture is mixed with 41.0 parts of dimethylbenzene-f «, fr) '- diisoxyanate (Mixture of 78 parts of the 1,3-isomer and 22 parts of the 1,4-isomer) below vigorous stirring, causing a reaction that produces a white, soft polyurethane foam crnibt.

Example 8 ^BelSpie14 . wnH

To 100 parts of polycaprolactone polyester ^ Iy ^ OM-hl 56 0 acid number 0.47 white waxy substance),

has been increased by U ^ ™haben ^ and Ρο ^ Λεφο ^ οΙ (produc

^ hI:! «» after

from

SSSn "mixed - if a reaction takes place, a white, soft polyurethane foam results.

Example 5

To 100 parts of the Polycaprolactonpolyesterpolyol mentioned in Example 4 are under strong

Stirring at 45 ° C 2.0 parts of castor oil-ethylene oxide adduct, 0.5 part of 2,5-di-tert-amylhydroquinone, 2.5 parts of water, 1.4 parts of 2 aminoethanol and 0.17 parts Octabutyldiisothiocyanatdiäthoxystannoxan given in this order. The mixture is then

to with 42.0 parts of dimethylbenzene-io.to'-diisocyanate (mixture of 78 parts of the 1,3-isomer and 22 parts of the 1,4-isomer) mixed with vigorous stirring, a reaction taking place resulting in a white, soft polyurethane foam.

Example 9

100 parts of the polyester polyol mentioned in Example 5 are mixed homogeneously with 3.0 parts of water, 2.0 parts of ao castor oil-ethylene oxide adduct and 0.5 part of 2,5-di-tert-amylhydroquinone. The • j _ .. »« or "- !, it. *" _N H then with 0.12 parts

Water,

C-tdlt . and 0,

™ _em is right. A reaction takes place here, which results in ^'icy ' ^{soft polyurethane foam}

^example

100 parts of one shafts of the im

₂ , 0 parts ri ^ nut oil

45.9 parts of dimethylbenzene ^ co-ds.socyanate (G mix of 75 parts of the 1,3-isomer and 25 parts of ₄₀ d part of the isomer) mixed with vigorous stirring. A reaction takes place here, which results in a white, soft polyurethane foam.

B ice _P ie 1 11

soft in polyurethane

9 10

Mechanical properties of polyurethane foams

I " 2 3 28.4
1.18
260
0.30 45.0
1.40
260
0.40 34.6
1.17
250
0.30 14.8 3.7 4.8 9.2 15.8 11.3 25.0
30.4
43.4 42.0
60.2
95.0 32.6
46.8
70.6 2.1 1.6 1.7

example

4 I 5 I 6 I 7

10 I.

Comparative experiment 1 I.

Rough weight, kg / m ³ ... Tensile strength, kg / cm * ...

Strain, %

Tear strength, kg / m .. deformation rest at

Compression, "/ o indentation load deflection, kg (JIS- * ^l -K-6401,
25% compression)

Pressure load, kg / cm *

25%

50%

65%

Loss of height in the fatigue test (flex fatigue loss of height) (ASTM D-1564 after 30 minutes),%

Chemical resistance to: i trichlorethylene against 1,1,1-trichloroethane

Heat resistance
(120 ⁰ C, 22 hours) ..

Weather resistance (after 3 months outdoors)

34.1

1.15 250

0.35

4.0

10.6

30.5 41.2 65.4

1.5

33.0
1.05
270
0.35 34.4
1.16
250
0.35 34.2
1.15
250
0.33 28 5
1.05
280
0.35 12.5 4.8 4.2 10.0 13.2 10.0 9.6 10.5 32.0
39.8
58.9 31.6
45.4
68.8 41.0
58.8
93.5 26.0
31.5
44.5 1.5 1.6 1.6 2.0

Well

Well

Well
■ not yellowed

28.2 1.20

280 0.33

10.0

9.5

26.5 32.1 44.8

2.0

33.5 0.85 240 0.25

7.5

9.1

26.0 32.0 48.0

2.3

2.

V)

O Cf

OQ

* 'Japanese industry standard.

·· It is impossible to measure the properties as there are strong cracks in the foams.

♦ ³ Essentially the same result is obtained when 1.0 part of 3-aminobutan-1-ol is used in place of 1.5 parts of 2-aminoethanol in Example 1.

Claims (2)

Patent claims: 1. Expired to manufacture polyurethane foams from Dimethylbenzoi-ft>, (. '/ - diisoi.vanat and a polyether polyol modified with a low molecular weight polyisocyanate in deficit having a hydroxyl number of about 25 to 75 or a polyester polyol having a Hydroxy number about 25 to 75 in the presence of amino alcohols and a propellant, thereby marked that one is in the presence a) a compound of the general formula RRRR X-Sn -O -Sn- X ' X "'- Sn-O - Sn-X ^1V R R R R where X '. X ". X" and X ^lv for halogen radicals, OH groups, low molecular weight alkoxy groups with a maximum of 4 carbon atoms, formyloxy. Alkylcarbonyloxy groups of 2 to 17 carbon atoms. NCO and NCS groups and R is a low molecular weight AlKyirest with a maximum of 4 carbon atoms. and b) a monoamino alcohol with a maximum of 4 carbon atoms is working. 2. The method according to claim I, characterized in that that the monoamino alcohol used is 2-aminoethanol or 3-aminobutan-1-ol.